ABSTRACT
DIFFERENTIAL DIAGNOSIS Prolapsed Disc Prolapsed disc is a common cause of severe lower back pain. The prolapsed disc often presses on a nerve root, which causes the pain and symptoms noted in the lower leg. The most common sites include L4/5 and L5/S1 disc areas. The patient may complain of back pain when he or she lifts a heavy object while unable to straighten their back thereafter. This can be accompanied by sciatic leg pain (sciatica) characterised by severe pain localised in the lumbar region or pain that radiates from the lower back down the back of either leg. Both the back pain as well as sciatica can be reproduced by coughing, sneezing or straining. Other features include the presence of a list to one side, limitation to forward fl exion and extension of the back and tenderness of the lower vertebrae in the back and paravertebral muscles. The straight leg raising test is an important test in detecting for a prolapsed disc and is limited on the affected side. Both Bragard’s test and Lasègue’s test can be used to confi rm the diagnosis of a prolapsed disc. There are a number of neurological signs that, if identifi ed, permit the examiner to localise the level of the prolapsed disc. Weakness of hallux extension with loss of sensation to the outer aspect of the leg and the dorsum of the foot suggests an L4/L5 level prolapse. Whereas pain in the calf, weakness to plantarfl exion and eversion of the foot, loss of sensation over the lateral aspect of the foot and depressed ankle refl ex suggest an L5/S1 level prolapse.
